40D and "*" focusing?

Is there any way to set the custom functions to separate the focusing of the camera from the shutter button, like what is discussed with the 20/30D? I am looking to focus with the " * " button. I've done it that way, long enough and don't want to relearn buttons.

Southswede wrote in post #3935425
Is there any way to set the custom functions to separate the focusing of the camera from the shutter button, like what is discussed with the 20/30D? I am looking to focus with the " * " button. I've done it that way, long enough and don't want to relearn buttons.

The 40D has an AF-ON button which can be used the same way the "*" button is used on the 20D/30D. To remove the AF from the shutter button, set C.Fn IV-1 to 2 if you want AE lock just before the picture is taken. Set it to 3 if you want AE to lock as soon as you half-press the shutter button.

If you don't like the feel of the AF-ON button and prefer the focusing to be done with the "*" button, then set C.Fn IV-2 to 1.

C.Fn.IV 1-2(3)
C.Fn.IV 2-1

Edit: I am too slow..

Thank you both very much!

Which mode do you prefer, IV-1 set to 2 or IV-1 set to 3?

banxai75 wrote in post #3935903
Which mode do you prefer, IV-1 set to 2 or IV-1 set to 3?

Depends on when you want your exposure to be metered. If you want your exposure to be determined and locked as soon as you press the shutter button, even half-way, then select 3. If you would rather have your exposure determined just before the picture is taken, then select 2.

I have mine set to 2.

I must be missing something here so please excuse my ignorance... but why not just use the AE lock button first, then press the shutter halfway to focus, then take the picture. Wouldn't exposure and focus be separated this way, which I thought was the point of these custom functions? Thanks!

^^^ Yes, but this way camera will refocus every time you press the shutter button, which may not be desirable.

dolomick wrote in post #4301804
I must be missing something here so please excuse my ignorance... but why not just use the AE lock button first, then press the shutter halfway to focus, then take the picture. Wouldn't exposure and focus be separated this way, which I thought was the point of these custom functions? Thanks!

Although exposure and focus would be separated, you would be constrained to set exposure first and then focus. With the other methods you can vary either as you please.

PacAce wrote in post #3936143
Depends on when you want your exposure to be metered. If you want your exposure to be determined and locked as soon as you press the shutter button, even half-way, then select 3. If you would rather have your exposure determined just before the picture is taken, then select 2.

I have mine set to 2.

wouldn't it be better to set to 3 so that you canmeter to check exposure level and then make adjustments as needed and/or meter off something close to 18% before recomposing? This is how I do it...but then again, I am just a beginner with very mixed "end results" usually.

slyone wrote in post #4304357
wouldn't it be better to set to 3 so that you canmeter to check exposure level and then make adjustments as needed and/or meter off something close to 18% before recomposing? This is how I do it...but then again, I am just a beginner with very mixed "end results" usually.

This took me a long while to understand till Rene on POTN explained it and i suddenly understood.
Setting 3 is great if your SURE the light on the metered subject will not change in the second or two before you press the shutter release from half way to fully down. But if your subject was in say bright sunlight when you half depressed the shutter button, and then a second later a little cloud passed over and put your subject into shade,,,,wrong exposure. = bad picture.
Setting 2 will have saved the shot, as exposure is metered the nano second you press the shutter. So if you were shooting say a band or performance where the lighting changes by the nanosecond, you will get more "keepers" using setting 2.

Use the "Force" Luke.........

Hope this explains it a little better, cheers, mark

Coastwatch203 wrote in post #4329801
This took me a long while to understand till Rene on POTN explained it and i suddenly understood.
Setting 3 is great if your SURE the light on the metered subject will not change in the second or two before you press the shutter release from half way to fully down. But if your subject was in say bright sunlight when you half depressed the shutter button, and then a second later a little cloud passed over and put your subject into shade,,,,wrong exposure. = bad picture.
Setting 2 will have saved the shot, as exposure is metered the nano second you press the shutter. So if you were shooting say a band or performance where the lighting changes by the nanosecond, you will get more "keepers" using setting 2.

And just to add to this very good explanation...if you want to have the best of both worlds you can, if you decide to, lock the exposure as in setting 3 by pressing the (*) button while in setting 2.

My head hurts!

I kinda feel like a noob for saying it, but the AE lock is pretty much useless when using manual mode, correct? Seeing as how the user has complete control over exposure and aperture, there are no other factors on how the camera exposes the shot. The camera still actively meters (I have my * set to AF and shutter set to AE, no AE lock i believe), but since it's in manual it doesn't change any settings.

SolidxSnake wrote in post #4330377
I kinda feel like a noob for saying it, but the AE lock is pretty much useless when using manual mode, correct? Seeing as how the user has complete control over exposure and aperture, there are no other factors on how the camera exposes the shot. The camera still actively meters (I have my * set to AF and shutter set to AE, no AE lock i believe), but since it's in manual it doesn't change any settings.

Yep, your right. I personally only use manual mode for flash photography, or long exposure shots,(lightening etc) or creative shots, or in a studio where i control the lighting.

At an event like a band performance i will use Tv, set a shutter speed / ISO fast enough to avoid blur, (depending on the lens i am using,) - and let the camera set the Apature + exposure.I get better results, more "Keepers" this way cause when the lighting changes the camera adjusts instantly if im in setting 2.

I use Av when i want to control DOF.

Don't get me wrong, manual's great, but in fast changing lighting conditions its just too slow to use! - near on impossible unless the lighting stayed the same for a while.

I don't hesitate to go to 1600 ISO if i need to, -as long as i can get the shutter speed to keep things sharp im happy!